The application is great when it works but unfortunately I too can confirm that it goes silent, with no recovery and does so I think 10/10 times when I press the lock button.
Restarting the app worked sometime but another time not which prompted me to turn off/on the phone. I downloaded it today so I'm guessing it must be 12.19 version. I'll try to take some time soon to amend the bug report with more details instead of here in the forum.
In summary I would not have voted for it to be presented as stable status.
Don't see this as negative. It really is a wonderful application and that's why I care about it and want to point out the need to understand whatever those problems are to bring it up to 5 stars.
Re: Reception quality - I have tried with standard Ipod headphones and then all the strong stations sounded great. Try a few different headphones and hopefully that will help out.

I just installed version 2009.12.19 and I experienced the same here, The lastest version is an improvement but the problem still exist especially when I lock the screen. I cant easily recreate the problem, but it seem to be unable to recover sound once it is lost due to interruption. Is there a way I can start the app from the commandline so I can via more infor on the issue